Nyaaori/rockbox
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

Disable UDMA 2 on iPod4G target

Browse source 
ATA DMA was enabled for all PP502x targets in d118f47 after previously reported instabilities were thought to have been fixed. The iPod 4G target remains unstable when UDMA 2 is enabled. File system corruption will eventually occur even using stock hardware in normal usage, according to both my own experience and that of several other forum users. UDMA 1 appears to be stable.

Change-Id: I8526bad9e879f5dad5174cfe07cd8828d8b72406
This commit is contained in:
Christian Soffke 2021-02-21 00:53:01 +01:00 committed by Solomon Peachy
parent 317908e8c3
commit 7d7850368e
1 changed files with 4 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
firmware/target/arm/pp/ata-target.h
View file

@ -63,13 +63,15 @@
/* Maximum multi-word DMA mode supported by the controller */
#define ATA_MAX_MWDMA 2
#ifndef BOOTLOADER
#ifndef BOOTLOADER
/* The PP5020 supports UDMA 4, but it needs cpu boosting and only
* improves performance by ~10% with a stock disk.
* UDMA 2 is stable at 30 Mhz.
* UDMA 1 is stable at 24 Mhz.
*
* A slower mode is used on iPod 4Gs due to reported instabilities.
*/
#if CPUFREQ_NORMAL >= 30000000
#if CPUFREQ_NORMAL >= 30000000 && !defined(IPOD_4G)
#define ATA_MAX_UDMA 2
#elif CPUFREQ_NORMAL >= 24000000
#define ATA_MAX_UDMA 1